Weather Conditions
Rain, snow, fog, hydroplaning, black ice
In Japan, heavy snowfall areas often require vehicles to carry tire chains even if they have winter tires.
🌧️ Weather Conditions Cheat Sheet
Key facts from this topic. Print this page for quick offline reference.
TRUE: Hydroplaning occurs when a layer of water builds up between the tires and the road surface, causing a loss of traction.
Hydroplaning (aquaplaning) happens when water accumulates between the tires and road faster than the tires can disperse it.
TRUE: The road is most slippery during the first few minutes of rainfall.
The road is most slippery when rain first begins because water mixes with oil, dust, and rubber residue on the road surface.
TRUE: In heavy rain, you should increase your following distance to at least double the normal distance.
In heavy rain, braking distances increase significantly.
TRUE: Black ice is a thin, transparent layer of ice on the road that is nearly invisible.
Black ice is a thin, nearly invisible layer of ice that forms on road surfaces, especially on bridges, overpasses, and shaded areas.
TRUE: When encountering strong crosswinds, you should grip the steering wheel firmly and reduce speed.
Strong crosswinds can push your vehicle off course.
TRUE: Bridges and overpasses tend to freeze before regular road surfaces.
Bridges and overpasses are exposed to cold air from above and below, causing them to freeze before regular road surfaces.
TRUE: When driving in heavy rain, you should turn on your headlights to increase your visibility to other drivers.
Turn on your headlights (low beams) in heavy rain to make your vehicle more visible to other drivers.
TRUE: In snowy conditions, sudden acceleration, braking, or steering can cause your vehicle to skid.
On snowy or icy roads, all inputs (acceleration, braking, steering) must be gentle and gradual.
TRUE: When driving through a flooded road section, you should drive slowly in a low gear.
If you must drive through shallow standing water, use a low gear and drive slowly at a constant speed to prevent water from entering the engine.
TRUE: After driving through water, your brakes may be less effective and should be tested gently.
Water can reduce brake effectiveness.
FALSE: When driving in fog, you should use high beams for maximum visibility.
In fog, use LOW beams (and fog lights if available).
FALSE: Snow tires or chains are recommended but not legally required in snowy conditions in Japan.
In areas with snow, using winter tires or tire chains is legally required.
FALSE: If your vehicle begins to hydroplane, you should brake firmly to regain control.
If hydroplaning, do NOT brake suddenly or turn sharply.
FALSE: During a typhoon, it is best to continue driving slowly rather than stopping.
During a severe typhoon, the safest option is to stop driving entirely.
FALSE: When driving in fog, you should follow the vehicle ahead closely to keep them in sight.
In fog, increase your following distance, not decrease it.